Electrical well logging is well known and various devices and various techniques have been described for this purpose. Properties of the formation may be estimated by creating electromagnetic (EM) excitation in the formation with at least one transmitter, and receiving related signals at one or more receiver antennas. Estimation of these properties aids in understanding the structure of the earth formation, which enables and/or facilitates exploration and development of the formation.
Historically, measurements of resistivity, or its inverse, conductivity, have been used for, among other reasons, inferring the fluid content of the earth formations and distances to bed boundaries. Also, lower conductivity (higher resistivity) measurements may be indicative of hydrocarbon-bearing earth formations.